What causes Prop Pox (and how to avoid it)

[M4346]

I usually save with CTRL + ALT + S periodically in-game (this is much faster because it doesn't update the region view and doesn't safe any data for the transportation view). I only use CTRL + S when I want the region view updated for screenshots and stuff. I never save with the button, always with the keyboard, and then exit without saving.

[APSMS]

At any rate, I wonder what really causes the missing traffic, whether it's actually related to Prop Pox or not, and if it's possible for vetted props to cause the Pox, or if something else is happening that is causing all of this (what it could be I have no idea).

In my case, the missing traffic and economic woes were the direct result of deleting those subfiles, which happen to be the network index and sims-to-jobs matching file. So as far as the game was concerned, when I loaded the city, there were no longer any networks (as evidenced by my totally blank traffic congestion data view), and all the residents were unemployed. No wonder most of them left town!

I didn't notice in you post that you deleted anything from your plugins file, except for the Quais de Seine trees from a long time ago. Why would those props have the network index/jobs files as part of their exemplars, or am I missing something obvious here (most likely)? Or rather, why would prop pox, which removes props after the prop exemplar file experiences an uncontrollable overflow, affect the network TGI/parameters?

IINM, that fix is by simmaster07, but yes, it's installed.

Oops, faux pas on my part. Sorry simmaster07.

[Mandarin(a)]

A quick update: After setting my city details to low and saving at zoom 1 (as recommended earlier in this thread), it appears that I can play my backup of the city without triggering the pox. Doing these two things also dramatically speeds up the saving process. So it looks like I'll be using these techniques in this city for a while to come (along with not using save-and-exit, which I've avoided for years now).

Yes, I have also read somewhere (I believe it was here on SC4D) that saving at zoom 1 and setting details to low speeds up the process of saving and helps to avoid the prop pox. This is probably because fewer props are "visible" in that case.

[dyoungyn]

I have personally tried this in the past and yes, it does re-set the Prop Pox, however, it also removes all the floral as in trees when you re-set it back to the default view. 

[speeder]

I saw about this on the dll thread at the other site...

I am not sure what is going on, I didn't read the entire thread (36 pages woot!!!)

Also I never had the issue, maybe because I don't have lots of graphical mods (including new lots), since I tend to focus on gameplay stuff.

Anyway, recently I've been STILL trying to track down the damned commute time bug, and while chasing it I ended stumbling on how the game saves stuff, since it is not related to what I am chasing now, I don't went in details...

But the game basically use something that resemble "save-state" that you see in console emulators, it copies whole chunks of memory, compresses it, and stores it, this includes even completely irrelevant information for when it is decompressed, like memory pointers, and stuff that have to be reset anyway (like the current CPU timestamp, used to know how much time passed since the last simulation update).

The "subfiles" people documented, are frequently a class, many classes in the game (but not all), inherit from a class called "Serializable", the game when saving basically memory dump entire classes on the save file.

The result of this, is that everything, and I mean EVERYTHING affects a safe file, the zoom level, what you were doing, the time of day in real world, the time in-game, the amount of props on screen, the amount of automata on screen, and so on.

Maxis basically was unsure of what to save, and decided to just save everything.

This has some side effects:

anything that was decided only once (for example during city creation), will stay that way, no matter how much you mod the .exe, add .dlls, edit .DATs, install or remove plugins, some stuff will just stay in that save file.

This is why sometimes if your save gets corrupted, you can't fix it, the corruption is saved in it, and will stay in it.

This also makes the general idea of installing and removing mods during play of a city, a bad idea, any mods that add or remove stuff that is saved only once, won't affect it, maybe to no effect, and maybe to causing bugs, since I have no idea what properties of a save file are calculated only once, I cannot advise about what type of mods cause bugs or not.


Another notable thing, is that because the save file is a memory dump, that is affected by almost everything, you must be careful to not save your file in some situations, for example if you are going beyond what the game can do (example: maybe you zoomed out, and there is not enough memory to display all props, or you have a crap GPU that don't have enough vram for all textures), it will save that "culled" information, or even corrupted information.

Also, if you save the game after something corrupting happened, it will save corrupted (example: your computer overheated, and started to glitch all over the place, any random stuff that the overheating changed on the memory, will be saved).

So what I can suggest is: if you care too much, make backups (I personally don't make them). And be careful when you save, if you abused the game in some manner (example, created some bizarre stuff with NAM or other complex mod, or tried all the cheats, or installed some crazy mods to see what they do), it is better to not save.

[Mandarin(a)]

Well that's interesting.

[woodb3kmaster]

I didn't notice in you post that you deleted anything from your plugins file, except for the Quais de Seine trees from a long time ago. Why would those props have the network index/jobs files as part of their exemplars, or am I missing something obvious here (most likely)? Or rather, why would prop pox, which removes props after the prop exemplar file experiences an uncontrollable overflow, affect the network TGI/parameters?

There seems to be some misunderstanding here. I'm not saying that I deleted anything from my plugins (not even the QS trees; I simply put the old versions in a folder that loads after the new ones). Rather, I deleted three subfiles from within my savegame, as per z's instructions from page 20 of this thread:

You can completely get rid of the pox any time you want... temporarily.  Here's how:

1. Open your saved city in Ilive's Reader.
2. Sort the left pane based on file size, with the highest at the top.
3. Near the top, there will be a subfile of type 2977AA47.  This is the prop subfile.  Delete it.
4. Also delete the subfiles of type 6A0F82B2 and 6990C1AA, which are also near the top.  These subfiles are regenerated as needed.  If you don't delete them, this process will still work, but your city size will increase greatly each time you repeat this process.
5. Save the city file.
6. Start up the game, but don't open the city file.
7. Open the Graphic Options, and make sure the City Detail is set to Low.
8. Open your city and save it immediately.
9. Exit to the region without saving.
10. Open the Graphic Options, and change your city detail to High.
11. Open your city.  All your props should be restored.
12. Save your city.  Your props will all be there... for a while.

Those two extra subfiles that the instructions say to delete are, as I mentioned, the network index subfile and the sims-to-jobs matching subfile. Prop pox doesn't affect them at all, but deleting them supposedly keeps the savegame from getting bloated (although that wasn't true for me; my edited savegame was over 35MB after I saved it). However, it also has the effects I described in my first post.

[Moonraker0]

I'm really confused and frustrated by the Prop Pox right now; it has occurred in my main region after three years of no instances of the bug.  I have been making about bi-weekly backups of the region for the past three years since I started it, at least during periods of time when I was playing SC4.  For at least the first year of play, I was rigorously checking all of the city files I'd played in SC4Save to see if there were any disabled props every time before I made a new backup, and there never were any.  Eventually, since I already had most of the plugins I wanted for the region, I stopped doing checking the files, and stopped adding new plugins to the game.

About one month ago, though, I noticed the full instantiation of the prop pox bug in one of my main cities in the region.  Unfortunately, looking at many of the older backups from previous months shows that many of the cities had positive values for the number of disabled props in the region.  The older backups don't have any disabled props.  What's strange is that if I load an old backup of the region (without any disabled props) and then load and save the main poxed city (after waiting a few minutes), the city then has around 300 disabled props.

It appeared to me, then, that the plugin which caused the prop pox must have been added after that backup was made, so I tested removing different plugins from my game and loading and saving the city in question.  Bizarrely, the same number of disabled props would show up for this city no matter how many plugins I removed—I even removed all the files from the Documents plugins folder AND all the ones from the game's installation directory and still got around 300 disabled props.

I really don't understand how the disabled props can initially appear in a city when there are no plugins installed whatsoever.  Perhaps the offending plugin(s) was(were) in the game's folder all along, and I'm only seeing new disabled props now because that mod was removed from the game?  The past month's worth of testing to find the source plugin(s) has proven unsuccessful, sadly.  I've tested the majority of the backups I'd made individually, mainly by binary testing (removing half of my plugins and testing the city).  Even with the oldest one, from early January of 2013, I get disabled props when I remove all of my plugins and test the only city in the region at that time.  I get between 100-200 of them if I do this, but if I leave the current set of plugins I've had in the folder (what I've been playing with for a long time), I only get 2 disabled props—but this is more than this city had between the original backup and the subsequent one; both backups showed 0 disabled props originally.

Can anybody help me to explain all of this?  I just want to find the cause of the bug in my plugins; if I have to re-start the region, I guess I'll do that, but I just need to find the bad plugin already.

[twalsh102]

Moonraker,
The only currently available file that is known to definitely cause Prop Pox is PEG-OWW2_BDK_RESOURCE.DAT.  There has been much speculation over the years that there have been other files that might have caused the Pox back at the dawn of the SC4 modding movement (primarily because there was evidence of the Pox, or something very similar, that was available before the PEG file was ever published), but if the speculation is correct, none of the these suspect early files are currently available.  There has also been speculation that other PEG files have also caused the Pox, but this has never been proved.

The most concise and complete explanation of the Pox is in the the very first post of this topic by BAP.  Probably more important that his explanation of what causes the Pox is hisexplanation of how to avoid it (or even fix the PEG file if you really need it),

Also very important to understand is that none of the other content that has been published by Pegasus has been found to cause the Pox.  Some of the posters on this topic have suggested that the best way to avoid the Pox is to not use any of the content created by Pegasus, but I have always felt that this is a gross overreaction.  Obviously players will do what they want (sometimes regardless of what is suggested by anyone else), but by not using any of the PEG content, these players are denying themselves the use of some very unique content that hasn't been touched by any other content creator (IMHO).

As far as whether you need to restart your region, that is the common wisdom.  There have been several people that have suggested "fixes" for a Poxed city, but most if not all of these fixes have proved to be only temporary.

Go back and read through the first couple of posts, and hopefully most or all of your questions will be answered.

[Moonraker0]

Thanks for your reply.  I actually have previously read all the posts in this thread, including re-reading the first few recently, but could not come to a solution based on any of it.  I thought that the presence of any disabled props at all means that the city is prop pox-infected and will eventually show the bug's symptoms.  Also, I didn't mention this in the last post I made, but I'd already corrected the BDK resource pack file based on bap's solution in one of the earlier posts (the one involving deleting the offending props, if I remember correctly).  I had corrected the BDK file before I even started this region in 2013, so that's why I thought there must be another cause somewhere in my plugins, but just like you said, it doesn't seem like anyone knows of another plugin that causes Prop Pox.  I'll definitely re-start my region, but I have a feeling the Prop Pox will still manage to show up in my cities, unfortunately.  It seems like there's just no escaping it when you use a lot of mods like I do 

[Missvanleider]

Hi,

Sorry to wake this thread but I have come to a dead end and need some advice. I bring pictures:



maxis country club sans tree cover...



maxis mayor house missing seemingly quite a lot

These lots are obviously affected by an issue. I have not had the file confirmed as causing prop pox in my plugins folder (or any from the same 'series')

I cannot currently download the savegame explorer from the lex as I am perma-logged in on my work pc and forgot the password - t(he reset goes to a work email and I am not at work) 

This city is the first tile in a newly developed region as my last region showed similar issues - maxis country club being the first affected lot I noiced there also.

The save file for the city is currently 34.2 MB, although as mentioned above I can't look more deeply at present.

Basically, I am looking for a confirmation that this (could be) prop pox, in which case there is another guilty file floating around - as I have never created content for myself it must be something I have downloaded and therefore must be worth flagging to the community.

Alternatively, someone offering an alternative explaination - some other kind of save file corruption - would also be helpful.

[vortext]

Typically pox affects a city over huge areas (see Feyss' recent encounter), making props disappear in wide strips which run all throughout the city tile. In other words, it rarely affects just one or two lots. If this were pox, I'd expect for instance to see props missing on the avenue, as well as the residential lots. From the looks of it, I'd say it's an issue with the Maxis rewards instead. Perhaps you have recently added reward replacements without bulldozing previous instances of them?

Then again, without confirmation from SC4SavegameExplorer my guess is as good as anybody's, really.

[Missvanleider]

I appreciate the response, I don't have anything which messes with the rewards to my knowledge as this tile has all been developed quite recently. I will get the save game explorer next week and have a better look

[vortext]

Since it only seems to affect Maxis' lots (the large park looks bare as well), and you had this happen previously, maybe the main game files are corrupted somehow. If you're comfortable with the idea you could try reinstalling the game all together, just make sure to back-up the plugins and regions folders beforehand. 

[Missvanleider]

Vortext. The re-install seems to have worked. Thank you so much!

[Moonraker0]

I was wondering if anyone can definitively tell me whether or not having a nonzero value for "disabled props" in a city tile means that it is prop pox-infected and will eventually show the symptoms of prop pox if the necessary conditions are met.  After the last run-in I had with the prop pox recently, I re-started my region.  Previously, I had just used iLive's Reader to correct the known cause (PEG BDK Resource Pack) to avoid the prop pox (this was years ago), but upon restarting the region, I just went ahead and deleted it, since that seemed to not be working out.  Now, in the brand-new region, I have disabled props showing in SC4Save in some of my cities.  I re-read the first few posts of the thread, but couldn't figure out if disabled props necessarily mean prop pox or if they have other uses in the game.  I guess I'd previously thought that the presence of disabled props meant that the city was infected.  Perhaps there is another cause of Prop Pox in my plugins after all.

[vortext]

Yeah I'm afraid disabled props in SC4Save means the city will get prop pox once the file size threshold is met, and as far as I know there's no way to somehow get rid of them, or re-enable the props before it's too late. 

[Wiimeiser]

Something I noticed a long time ago: God Mode data doesn't appear to use checksums. Or at the very least, you can corrupt a city so that its tile disappears, open the tile in SC4Terraformer, and, as long as you revert the tile to God Mode it will reappear. Not sure if this is really all that relevant, but we might be able to figure out a lot more, possibly even a fix, by checking out the checksums.

EDIT: On a more on-topic note, what would happen if you obliterated a city with the pox and immediately started a new one without saving or leaving the tile? Would it carry over?

[vortext]

iirc obliterating a city only makes things worse because it marks all props as disabled. 

[markussaage]

I've got a city tile, that only has layed out with some roads and streets and zoned with some Res and Com areas. I've never played it further, so this city hat no buildings grown or plopped and it has no residents. Curious about the SC4 Save Explorer tool I opened it and found 5 disabled props counted in the tool.
Are street/road tiles counted as props as well? I might have deleted some before I saved this city a while back.
Anyone has an explanation for this? Just curious you know...

Kind regards!